This disclosure relates generally to securing an auxiliary power unit.
Turbomachines extract energy from a flow of fluid. During operation, air is pulled into the turbomachine. The air is then compressed and combusted. The products of combustion expand to rotatably drive a turbine section of the turbomachine.
One example turbomachine is an auxiliary power unit (APU). An APU may be located in the tail section or elsewhere on a commercial aircraft. The APU provides electrical power and compressed air to the aircraft.
During operation, the APU is exposed to extreme temperatures and other harsh operating conditions. Tests have been developed to ensure that the APU and its associated components will respond appropriately when facing such conditions. Tests are continually revised and new tests are added. Passing these tests can be difficult, especially when using retrofitted APUs and retrofitted components.